uf2tool portability issues

[TomKeddie]

I don't see what platforms uf2tool builds for but it looks specifically written for osx and won't build on linux. This should probably be noted in the README.

[tom@z400 uf2tool]$ make
mkdir -p ../built
cc -g -Wall tool.c ../hidapi/mac/hid.c -I../../uf2-samd21/inc -I../hidapi/hidapi -I. -framework IOKit -framework CoreFoundation -o ../built/uf2tool
cc: error: IOKit: No such file or directory
cc: error: CoreFoundation: No such file or directory
cc: error: unrecognized command line option '-framework'
cc: error: unrecognized command line option '-framework'
make: *** [Makefile:3: all] Error 1
[tom@z400 uf2tool]$

I tried tidying the Makefile but the hidapi seems also to be reverting to osx.
.
.
../hidapi/mac/hid.c:25:36: fatal error: IOKit/hid/IOHIDManager.h: No such file or directory
#include <IOKit/hid/IOHIDManager.h>

I am running archlinux.

[tom@z400 uf2tool]$ uname -a
Linux z400 4.10.10-1-ARCH #1 SMP PREEMPT Wed Apr 12 18:50:28 CEST 2017 x86_64 GNU/Linux

edit
This line builds ok for linux.

$(CC) -g -Wall tool.c ../hidapi/linux/hid.c -I../../uf2-samd21/inc -I../hidapi/hidapi -ludev -lpthread -o ../built/uf2tool

[vkottler]

I ran into this also, decided to look at the Python implementation (see: #42 also).